DE 198 54 211A1 shows a hinge for a vehicle flap, in which a first hinge part is arranged on the tailgate and a second hinge part is arranged on a body part, the first hinge part and the second hinge part being connected to each other pivotably by means of a hinge pin. Provided on the first hinge part parallel to the hinge pin is a bearing sleeve, in which a locating bolt supporting a three-dimensionally coiled spiral spring is rotatably mounted. A first end section of the spiral spring bears with prestress against the hinge pin and a second end section is supported with prestress on a bearing pin arranged on the bearing sleeve. Furthermore, arranged on the locating bolt is a first lever which is coupled pivotably to a second lever arranged on the second hinge part. A disadvantage with this type of hinge is the fact that only a support of the opening movement of the vehicle flap is possible by the spiral spring. By contrast, during closing of the vehicle flap the spiral spring has to be prestressed again, as a result of which, during the closing movement, a force resulting from the bending force of the spring has to be overcome. Furthermore, the arrangement of the levers and locating bolts on both sides of the pivot mounting of the hinge parts is complicated in terms of installation and does not permit retrofitting. A possibility of arresting the flap in a partially open position is not envisaged.
DE 197 44 908 A describes a drive device for a front flap or tailgate of a motor vehicle, comprising a flap hinge, in which the pin of a hinged joint corresponds to the transmission output shaft of a drive motor which, like the hinged joint, is arranged in the region of a stop part on the body. A disadvantage of this device is, in particular, the space required by the motor in the region of the stop parts on the body, since said stop parts are generally arranged on the outside as far as possible and therefore do not permit the arrangement of a motor or permit it only under very unfavorable conditions, for example in the wing outside the trunk, with the shaft for this having to be guided through the body sheet and having to be sealed and there being hardly any protection against dirt and water.
WO 01 81 699 A1 describes a drivable flap hinge for an articulated connection of a flap, in which a first hinge part and a second hinge part are coupled pivotably to each other via a first link and a second link which are arranged in the manner of a four-bar hinge. A pin of a hinged joint of the first link to the hinge part arranged on the flap is designed as a drive shaft for a drive motor. The drive motor is arranged in a housing in the region of the first link, the drive motor being arranged with the housing on that side of the first link to the hinge part arranged on the body and being able to pivot past the second link.